Apparatus and method for reducing UE&#39;s power consumption by controlling early decoding boundary

ABSTRACT

Disclosed are methods and apparatus for reducing UE&#39;s power consumption by controlling early decoding boundary. In one aspect, a UE is configured to receive a data or voice frame from a base station. The UE selects one or more quality metrics for determining decoding boundary of the received frame and computes the selected one or more quality metrics. The UE then determines a decoding boundary for the frame based on one or more computed quality metrics. The UE then decodes the received frames at the determined decoding boundary and determines whether the decoding of the frame was successful. If the early decoding of the frame was successful, the UE may terminate reception of the frame. If the early decoding of the frame was unsuccessful, the UE may adjust the decoding boundary and decodes the frame at the adjusted boundary.

CLAIM OF PRIORITY UNDER 35 U.S.C. §119

The present application for patent claims priority to ProvisionalApplication No. 61/703,480 entitled “Apparatus and Method for ReducingUE's Power Consumption by Controlling Early Decoding boundary” filed onSep. 20, 2012, and assigned to the assignee hereof and hereby expresslyincorporated by reference herein.

BACKGROUND

1. Field

Aspects of the present disclosure relate generally to wirelesscommunication systems, and more particularly, to an apparatus and methodfor reducing UE's power consumption by controlling early decodingboundary.

2. Background

Wireless communication networks are widely deployed to provide variouscommunication services such as telephony, video, data, messaging,broadcasts, and so on. Such networks, which are usually multiple accessnetworks, support communications for multiple users by sharing theavailable network resources. One example of such a network is the UMTSTerrestrial Radio Access Network (UTRAN). The UTRAN is the radio accessnetwork (RAN) defined as a part of the Universal MobileTelecommunications System (UMTS), a third generation (3G) mobile phonetechnology supported by the 3rd Generation Partnership Project (3GPP).The UMTS, which is the successor to Global System for MobileCommunications (GSM) technologies, currently supports various airinterface standards, such as Wideband-Code Division Multiple Access(WCDMA), Time Division-Code Division Multiple Access (TD-CDMA), and TimeDivision-Synchronous Code Division Multiple Access (TD-SCDMA). The UMTSalso supports enhanced 3G data communications protocols, such as HighSpeed Packet Access (HSPA), which provides higher data transfer speedsand capacity to associated UMTS networks. High Speed Downlink PacketAccess (HSDPA) is a data service offered on the downlink of WCDMAnetworks.

Some WCDMA systems provide early voice frame termination functionalityby which early decoding on voice transport channels is attempted by theUE receiver, so that the receiver may be transitioned into a low-powerstate to preserver batter power if the early decoding of the voice frameis deemed successful. Therefore, it is possible to reduce receiver'spower consumption by controlling early decoding boundary.

SUMMARY

The following presents a simplified summary of one or more aspects inorder to provide a basic understanding of such aspects. This summary isnot an extensive overview of all contemplated aspects, and is intendedto neither identify key or critical elements of all aspects nordelineate the scope of any or all aspects. Its sole purpose is topresent some concepts of one or more aspects in a simplified form as aprelude to the more detailed description that is presented later.

Disclosed are methods and apparatus for reducing UE's power consumptionby controlling early decoding boundary. In one aspect, a UE isconfigured to receive a data or voice frame from a base station. The UEselects one or more quality metrics for determining decoding boundary ofthe received frame and computes the selected one or more qualitymetrics. The UE then determines a decoding boundary for the frame basedon one or more computed quality metrics. The UE then decodes thereceived frames at the determined decoding boundary and determineswhether the decoding of the frame was successful. If the early decodingof the frame was successful, the UE may terminate reception of theframe. If the early decoding of the frame was unsuccessful, the UE mayadjust the decoding boundary and decodes the frame at the adjustedboundary.

To the accomplishment of the foregoing and related ends, the one or moreaspects comprise the features hereinafter fully described andparticularly pointed out in the claims. The following description andthe annexed drawings set forth in detail certain illustrative featuresof the one or more aspects. These features are indicative, however, ofbut a few of the various ways in which the principles of various aspectsmay be employed, and this description is intended to include all suchaspects and their equivalents.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosed aspects will hereinafter be described in conjunction withthe appended drawings, provided to illustrate and not to limit thedisclosed aspects, wherein like designations denote like elements, andin which:

FIG. 1 is a block diagram that illustrates one example implementation ofa user equipment.

FIG. 2 is a block diagram that illustrates a DTCH frame structureshowing various decoding boundaries.

FIG. 3 is a block diagram that illustrates one example implementation ofan early decode assessment module.

FIG. 4 is a flow chart that illustrates an example method fordetermining frame decoding boundary.

FIG. 5 is a block diagram illustrating an example of a hardwareimplementation for an apparatus employing a processing system configureddetermine frame decoding boundary.

FIG. 6 is a block diagram conceptually illustrating an example of atelecommunications system including an aspect of the user equipmentconfigured to determine frame decoding boundary.

FIG. 7 is a conceptual diagram illustrating an example of an accessnetwork including a user equipment configured to determine framedecoding boundary.

FIG. 8 is a block diagram conceptually illustrating an example of a NodeB in communication with a UE in a telecommunications system, wherein theuser equipment is configured to determine frame decoding boundary.

DETAILED DESCRIPTION

Various aspects are now described with reference to the drawings. In thefollowing description, for purposes of explanation, numerous specificdetails are set forth in order to provide a thorough understanding ofone or more aspects. It may be evident, however, that such aspect(s) maybe practiced without these specific details.

FIG. 1 illustrates an example configuration of a user equipment (UE) 10.UE 10 includes a RF antenna 11 that receives RF signals, such as WCDMAvoice or data packets and pilot signals, from a base station andtransforms them into electromagnetic signals. The signals aretransmitted to amplifier circuit 12, which may include a low noiseamplifier (LNA), analog-to-digital converter (ADC), variable gainamplifier (VGA) and automatic gain control (AGC) circuit, whichcalibrates operating range of the LNA, ADC and VGA. The amplified anddigitized signals are then passed to a Rake receiver 13, which isdesigned to mitigate the effects of multipath fading. Rake receiver 13may include a path search for identifying different propagation paths ofthe signal, a channel estimator that estimate channel conditions, suchas time delay, amplitude and phase for each path component, and a pathcombiner that combines strongest multipath components of the receivedsignal into one signal. The resulting signal is then demodulated by ademodulator 16, such as a QPSK demodulator, equalizer, ormulti-user/code detector. The demodulated signal is passed to decoder17, such as Viterbi decoder, which performs decoding of theconvolutionally encoded data used in WCDMA transmissions. In one aspect,the Rake receiver 13, demodulator 16 and decoder 17 may be implementedusing a Digital Signal Processor (DSP). The UE 10 also includes aprocessor 14, such as a microprocessor, microcontroller, or CPU, whichexecutes programs for controlling operation of the components of the UE,and memory 15 that stores data and programs executed by the processor14.

As mentioned above, some WCDMA systems provide early voice frametermination functionality that allows UE 10 to perform early decoding ofdata on voice and data transport channels, so that the receivercircuitry of UE 10 may be transitioned into a low-power state topreserver UE's batter power if the early decode of the received data orvoice frames is deemed successful. This is illustrated in FIG. 2. Thebase station divides voice or data into blocks, which are encoded andtransmitted to the UE 10 on a Downlink (DL) Dedicated Traffic Channel(DTCH) as one or more frames. Each DTCH frame has duration oftransmission time interval (TTI), which may span one, two, four, oreight 10 ms slots. A depicted, the UE 10 can attempt to decode the DTCHframes as early as at 8 ms into the TTI. This decode time is known as adecoding boundary. If the DTCH frame has been successfully decoded, theUE 10 may power down its receiver circuitry to conserve battery.However, if an early decode of the DTCH frame has failed, UE 10 canattempt to decode the DTCH at a later decoding boundary, e.g., 10 ms, 12ms or 14 ms boundary, which will require UE 10 to operate in high powermode for a longer time and therefore consumer more battery power.

Therefore, it is desirable to dynamically control DTCH decoding boundaryin order to prevent unnecessary early decodes and optimize UE's powerconsumption. To that end, in one implementation, the UE 10 includes adecoding boundary assessment module 18 that determines proper decodingboundary for DTCH frames based on various transmission quality metrics(M), including, but not limited to: decoder quality metric,Signal-to-Interference Ratio (SIR) metric, Symbol Error Rate (SER)metric, encoding rate metric, and other types of metrics, such ascomputation and power metrics.

FIG. 3 shows one example implementation of the decoding boundaryassessment module 18. The module 18 may include the followingsub-modules: SIR metric determiner 31, decoding metric determiner 32,encoding metric determiner 33, SER metric determiner 34, computationmetric determiner 35, power metric determiner 36 and metric combiner 37.In one aspect, the SIR metric determiner 31 estimatessignal-to-interference ratio (SIRE) from a common and/or dedicated pilotchannels. For instance, signal power may be estimated based on thecommon pilot. And, the noise-and-interference power may be determined asa difference between two successive pilots. The SIR metric determiner 31may compare the SIRE with SIR Target (SIRT) to determine whether toperform early decode of the DTCH frames. For example, if SIRE−SIRT>3 dB,decode at 8 ms boundary, else start decodes at 10 ms boundary.

In another aspect, the decoding metric determiner 32 may use Viterbidecoder path metrics, such as best and second best paths on the trellisdiagram, to determine quality of the received signals and theappropriate decoding boundary for the DTCH frames. For example, if a 10ms decode of DTCH frame was in error, the receiver may try only 14 msdecodes for all subsequent DTCH frames until signal quality improves, asdetermined by the decoding metric determiner 32. Particularly,determiner 32 may identify when the first best path on the Trellisdiagram significantly better then the second best path, which indicatesimprovement in received signal quality. When this takes place, thereceiver may switch back to early, e.g., 10 ms, decodes and poweringdown the receiver if early decode is successful. Alternatively, ifdecoding metric determiner 32 determines that on the last decode bestpath metric (at 10 ms) minus second best path (at 10 ms) less than aThreshold, then switch back to 14 ms decodes.

In another aspect, the encoding metric determiner 33 may use informationabout the type of encoding combined with SIRE measurement to select theappropriate decoding boundary for the DTCH frames. Particularly,full-rate voice encoding typically requires high SIR while silencedescriptor (SID) transmissions and Null transmissions require a muchlower SIR for decoding. Therefore, if a full-rate encoded transmissionis detected and SIRE−SIRT<0 dB, then decode full-rate transmission at 14ms only. However, in case of SID or Null transmissions, early decode,e.g., at 10 ms, may be performed if SIRE−SIRT<0 dB.

In another aspect, the SER metric determiner 34 may use symbol errorrate (SER) to determine the appropriate decoding boundary for the DTCHframes. SER indicates the difference between the best path in thedecoder trellis and the hard decoded bits. Typically, high SER is anindicator of a poor quality radio channel between a base station and aUE. Even in case of correct early decoding of a DTCH frame, the SER maybe high, which indicates that successful early decode was an anomaly andthe DTCH frames should be decoded at a later decoding boundary, e.g., 14ms. Thus, for example, the SER metric determiner 34 may determine if at10 ms decode, the SER>Threshold, then attempt only 14 ms decode on thecurrent and subsequent DTCH frames.

In another aspect, the computation metric determiner 35 may determinewhat additional computing resources (e.g., processing time) that may beconsumed by one or more of the amplifier circuit 12, Rake receiver 13,processor 14, demodulator 16, decoder 17 and/or other components of UE10 to perform additional (early or late) decodes of DTCH frames thatimpact other operations of the UE 10. For example, if computation metricdeterminer 35 determines that the raw DSP computations are nearing thepeak limit at a given low power setting, than determiner 35 may limitthe number of early decode attempts to prevent need to increase theclock speed or voltage level of the DSP. In another example, if the UEis in a scenario where there are a large number of blocks requiringearly decode attempt vs. a small number of blocks, then determiner 35may again limit the number of early decode attempts.

Yet in another aspect, the power metric determiner 36 may estimateadditional battery power that may be consumed by one or more of theamplifier circuit 12, Rake receiver 13, processor 14, demodulator 16,decoder 17 and/or other components of UE 10 to perform additional (earlyor late) decodes of DTCH frames that impact other operations of the UE10. For example, if the power metric determiner 26 determines that thepower cost of an early decode attempt is very small, then determiner 26may implement an algorithm which allows a larger number of early decodeattempts.

Yet in another aspect, the metric combiner 37 may combine, using acombining function (F), multiple quality metrics (M) provided by the oneor more of the SIR metric determiner 31, decoding metric determiner 32,encoding metric determiner 33, SER metric determiner 34, computationmetric determiner 35 and/or power metric determiner 36 to determine theappropriate decoding boundary (TDecode) for the DTCH frame that willprevent unnecessary (erroneous) early decodes and optimize powerconsumption of UE 10. The decoding boundary function may be representedas follows: T_(Decode)=F(M₁, M₂, M₃, . . . , M_(N)). For example, asimple decoding boundary function may look like: T_(Decode)=(SIRE>SIRT+3dB). This decode boundary function F chooses the decode boundary(T_(Decode)) to be a function of the excess SIRE over the SIRT and mutevs. voice traffic. For example, if SIRE is more than 3 dB above SIRT andUE 10 is not currently receiving any voice traffic, then decodingboundary function F may try to perform more earlier decode attempts,e.g., at 8 ms and 10 ms. However if UE 10 is receiving voice traffic orSIRE is not much more than SIRT, then decoding boundary function F maynot try to decode at 8 ms and wait for a later time for the first decodeattempt. This is an example of how the decode boundary T could be afunction of different quality metrics (SIRE, SIRT and MUTE/Voicetraffic). The function F may be optimized offline in a simulationenvironment or may be adaptively tuned over time based on actual decodesuccess/failure measurements in diverse channel environments.

FIG. 4 is an example method 40 for determining decoding boundary forDTCH frames. For example, in an aspect, methodology 40 may be executedby UE and/or components thereof, such as UE 10 (FIG. 1), one or morereceiver components, and power control module 18 (FIGS. 1 and 3). Atstep 41, the method 40 includes a UE receiving a DTCH data or voiceframe from a base station. For example, referring to FIG. 1, a UE mayuse RF antenna 11, power amplifier 12, Rake receiver 13 and demodulator16 to receive and demodulate signals from a base station. At step 42,the method 40 selects one or more quality metrics (M) for determiningdecoding boundary for the frame. For example, referring to FIGS. 1 and3, a UE may use decoding boundary assessment module 18 to select one ormore quality metrics. At step 43, the method 40 computes one or moreselected quality metrics. For example, referring to FIGS. 1 and 3, a UEmay compute quality metrics using one or more of the metric determiners31-36. If several metrics are computed, at step, 44 the method 40combines the computed quality metrics using a combining functions. Forexample, referring to FIGS. 1 and 3, a UE may use metric combiner 37 tocombine several quality metrics. At step 45, the method 40 determines oradjusts frame decoding boundary based on the combined metric. Forexample, referring to FIGS. 1 and 3, a UE may use decoding boundaryassessment module 18 to adjust frame decoding boundary. At step 46, themethod 40 decodes DTCH frame at the determined/adjusted boundary. Forexample, referring to FIGS. 1 and 3, a UE may use decoder 17 to decodeframe at the specified boundary. If it is determined at step 47 that theframe has been decoded successfully, the method 40 terminates framereception at step 49. If it is determined at step 47 that the frame wasnot decoded successfully, the method 40 adjusts (e.g. increases), thedecoding boundary at step 48, and repeats the attempt frame decode atthe new boundary at step 46. For example, referring to FIGS. 1 and 3, aUE may use decoding boundary assessment module 18 to adjust framedecoding boundary.

FIG. 5 is a block diagram illustrating an example of a hardwareimplementation for an apparatus 100, such as a UE, employing aprocessing system 114. Apparatus 100, which may be UE 10 (FIG. 1),employing a processor system 114 that executes the apparatus and methodsdescribed herein, including the functionality of decoding boundaryassessment module 18 (FIGS. 1 and 3). In this example, the processingsystem 114 may be implemented with a bus architecture, representedgenerally by the bus 102. The bus 102 may include any number ofinterconnecting buses and bridges depending on the specific applicationof the processing system 114 and the overall design constraints. The bus102 links together various circuits including one or more processors,represented generally by the processor 104, and computer-readable media,represented generally by the computer-readable medium 106. The bus 102may also link various other circuits such as timing sources,peripherals, voltage regulators, and power management circuits, whichare well known in the art, and therefore, will not be described anyfurther. A bus interface 108 provides an interface between the bus 102and a transceiver 110. The transceiver 110 provides a means forcommunicating with various other apparatus over a transmission medium.Depending upon the nature of the apparatus, a user interface 112 (e.g.,keypad, display, speaker, microphone, joystick) may also be provided.

The processor 104 is responsible for managing the bus 102 and generalprocessing, including the execution of software stored on thecomputer-readable medium 106. The software, when executed by theprocessor 104, causes the processing system 114 to perform the variousfunctions described infra for any particular apparatus. Thecomputer-readable medium 106 may also be used for storing data that ismanipulated by the processor 104 when executing software.

The various concepts presented throughout this disclosure may beimplemented across a broad variety of telecommunication systems, networkarchitectures, and communication standards. By way of example andwithout limitation, the aspects of the present disclosure may beimplemented by the UE illustrated in FIG. 6, which is presented withreference to a UMTS system 200 employing a W-CDMA air interface. A UMTSnetwork includes three interacting domains: a Core Network (CN) 204, aUMTS Terrestrial Radio Access Network (UTRAN) 202, and User Equipment(UE) 210. In this example, the UTRAN 202 provides various wirelessservices including telephony, video, data, messaging, broadcasts, and/orother services. The UTRAN 202 may include a plurality of Radio NetworkSubsystems (RNSs) such as an RNS 207, each controlled by a respectiveRadio Network Controller (RNC) such as an RNC 206. Here, the UTRAN 202may include any number of RNCs 206 and RNSs 207 in addition to the RNCs206 and RNSs 207 illustrated herein. The RNC 206 is an apparatusresponsible for, among other things, assigning, reconfiguring andreleasing radio resources within the RNS 207. The RNC 206 may beinterconnected to other RNCs (not shown) in the UTRAN 202 throughvarious types of interfaces such as a direct physical connection, avirtual network, or the like, using any suitable transport network.

Communication between a UE 210, which may be similar to UE 10 (FIG. 1)and including decoding boundary assessment module 18 (FIGS. 1 and 3),and a Node B 208 may be considered as including a physical (PHY) layerand a medium access control (MAC) layer. Further, communication betweena UE 210 and an RNC 206 by way of a respective Node B 208 may beconsidered as including a radio resource control (RRC) layer. In theinstant specification, the PHY layer may be considered layer 1; the MAClayer may be considered layer 2; and the RRC layer may be consideredlayer 3. Information hereinbelow utilizes terminology introduced in theRRC Protocol Specification, 3GPP TS 25.331 v9.1.0, incorporated hereinby reference.

The geographic region covered by the RNS 207 may be divided into anumber of cells, with a radio transceiver apparatus serving each cell. Aradio transceiver apparatus is commonly referred to as a Node B in UMTSapplications, but may also be referred to by those skilled in the art asa base station (BS), a base transceiver station (BTS), a radio basestation, a radio transceiver, a transceiver function, a basic serviceset (BSS), an extended service set (ESS), an access point (AP), or someother suitable terminology. For clarity, three Node Bs 208 are shown ineach RNS 207; however, the RNSs 207 may include any number of wirelessNode Bs. The Node Bs 208 provide wireless access points to a CN 204 forany number of mobile apparatuses. Examples of a mobile apparatus includea cellular phone, a smart phone, a session initiation protocol (SIP)phone, a laptop, a notebook, a netbook, a smartbook, a personal digitalassistant (PDA), a satellite radio, a global positioning system (GPS)device, a multimedia device, a video device, a digital audio player(e.g., MP3 player), a camera, a game console, or any other similarfunctioning device. The mobile apparatus is commonly referred to as a UEin UMTS applications, but may also be referred to by those skilled inthe art as a mobile station, a subscriber station, a mobile unit, asubscriber unit, a wireless unit, a remote unit, a mobile device, awireless device, a wireless communications device, a remote device, amobile subscriber station, an access terminal, a mobile terminal, awireless terminal, a remote terminal, a handset, a terminal, a useragent, a mobile client, a client, or some other suitable terminology. Ina UMTS system, the UE 210 may further include a universal subscriberidentity module (USIM) 211, which contains a user's subscriptioninformation to a network. For illustrative purposes, one UE 210 is shownin communication with a number of the Node Bs 208. The DL, also calledthe forward link, refers to the communication link from a Node B 208 toa UE 210, and the UL, also called the reverse link, refers to thecommunication link from a UE 210 to a Node B 208.

The CN 204 interfaces with one or more access networks, such as theUTRAN 202. As shown, the CN 204 is a GSM core network. However, as thoseskilled in the art will recognize, the various concepts presentedthroughout this disclosure may be implemented in a RAN, or othersuitable access network, to provide UEs with access to types of CNsother than GSM networks.

The CN 204 includes a circuit-switched (CS) domain and a packet-switched(PS) domain. Some of the circuit-switched elements are a Mobile servicesSwitching Centre (MSC), a Visitor location register (VLR) and a GatewayMSC. Packet-switched elements include a Serving GPRS Support Node (SGSN)and a Gateway GPRS Support Node (GGSN). Some network elements, like EIR,HLR, VLR and AuC may be shared by both of the circuit-switched andpacket-switched domains. In the illustrated example, the CN 204 supportscircuit-switched services with a MSC 212 and a GMSC 214. In someapplications, the GMSC 214 may be referred to as a media gateway (MGW).One or more RNCs, such as the RNC 206, may be connected to the MSC 212.The MSC 212 is an apparatus that controls call setup, call routing, andUE mobility functions. The MSC 212 also includes a VLR that containssubscriber-related information for the duration that a UE is in thecoverage area of the MSC 212. The GMSC 214 provides a gateway throughthe MSC 212 for the UE to access a circuit-switched network 216. TheGMSC 214 includes a home location register (HLR) 215 containingsubscriber data, such as the data reflecting the details of the servicesto which a particular user has subscribed. The HLR is also associatedwith an authentication center (AuC) that contains subscriber-specificauthentication data. When a call is received for a particular UE, theGMSC 214 queries the HLR 215 to determine the UE's location and forwardsthe call to the particular MSC serving that location.

The CN 204 also supports packet-data services with a serving GPRSsupport node (SGSN) 218 and a gateway GPRS support node (GGSN) 220.GPRS, which stands for General Packet Radio Service, is designed toprovide packet-data services at speeds higher than those available withstandard circuit-switched data services. The GGSN 220 provides aconnection for the UTRAN 202 to a packet-based network 222. Thepacket-based network 222 may be the Internet, a private data network, orsome other suitable packet-based network. The primary function of theGGSN 220 is to provide the UEs 210 with packet-based networkconnectivity. Data packets may be transferred between the GGSN 220 andthe UEs 210 through the SGSN 218, which performs primarily the samefunctions in the packet-based domain as the MSC 212 performs in thecircuit-switched domain.

An air interface for UMTS may utilize a spread spectrum Direct-SequenceCode Division Multiple Access (DS-CDMA) system. The spread spectrumDS-CDMA spreads user data through multiplication by a sequence ofpseudorandom bits called chips. The “wideband” W-CDMA air interface forUMTS is based on such direct sequence spread spectrum technology andadditionally calls for a frequency division duplexing (FDD). FDD uses adifferent carrier frequency for the UL and DL between a Node B 208 and aUE 210. Another air interface for UMTS that utilizes DS-CDMA, and usestime division duplexing (TDD), is the TD-SCDMA air interface. Thoseskilled in the art will recognize that although various examplesdescribed herein may refer to a W-CDMA air interface, the underlyingprinciples may be equally applicable to a TD-SCDMA air interface.

An HSPA air interface includes a series of enhancements to the 3G/W-CDMAair interface, facilitating greater throughput and reduced latency.Among other modifications over prior releases, HSPA utilizes hybridautomatic repeat request (HARQ), shared channel transmission, andadaptive modulation and coding. The standards that define HSPA includeHSDPA (high speed downlink packet access) and HSUPA (high speed uplinkpacket access, also referred to as enhanced uplink, or EUL).

HSDPA utilizes as its transport channel the high-speed downlink sharedchannel (HS-DSCH). The HS-DSCH is implemented by three physicalchannels: the high-speed physical downlink shared channel (HS-PDSCH),the high-speed shared control channel (HS-SCCH), and the high-speeddedicated physical control channel (HS-DPCCH).

Among these physical channels, the HS-DPCCH carries the HARQ ACK/NACKsignaling on the uplink to indicate whether a corresponding packettransmission was decoded successfully. That is, with respect to thedownlink, the UE 210 provides feedback to the node B 208 over theHS-DPCCH to indicate whether it correctly decoded a packet on thedownlink.

HS-DPCCH further includes feedback signaling from the UE 210 to assistthe node B 208 in taking the right decision in terms of modulation andcoding scheme and precoding weight selection, this feedback signalingincluding the CQI and PCI.

“HSPA Evolved” or HSPA+ is an evolution of the HSPA standard thatincludes MIMO and 64-QAM, enabling increased throughput and higherperformance. That is, in an aspect of the disclosure, the node B 208and/or the UE 210 may have multiple antennas supporting MIMO technology.The use of MIMO technology enables the node B 208 to exploit the spatialdomain to support spatial multiplexing, beamforming, and transmitdiversity.

Multiple Input Multiple Output (MIMO) is a term generally used to referto multi-antenna technology, that is, multiple transmit antennas(multiple inputs to the channel) and multiple receive antennas (multipleoutputs from the channel). MIMO systems generally enhance datatransmission performance, enabling diversity gains to reduce multipathfading and increase transmission quality, and spatial multiplexing gainsto increase data throughput.

Spatial multiplexing may be used to transmit different streams of datasimultaneously on the same frequency. The data steams may be transmittedto a single UE 210 to increase the data rate or to multiple UEs 210 toincrease the overall system capacity. This is achieved by spatiallyprecoding each data stream and then transmitting each spatially precodedstream through a different transmit antenna on the downlink. Thespatially precoded data streams arrive at the UE(s) 210 with differentspatial signatures, which enables each of the UE(s) 210 to recover theone or more the data streams destined for that UE 210. On the uplink,each UE 210 may transmit one or more spatially precoded data streams,which enables the node B 208 to identify the source of each spatiallyprecoded data stream.

Spatial multiplexing may be used when channel conditions are good. Whenchannel conditions are less favorable, beamforming may be used to focusthe transmission energy in one or more directions, or to improvetransmission based on characteristics of the channel. This may beachieved by spatially precoding a data stream for transmission throughmultiple antennas. To achieve good coverage at the edges of the cell, asingle stream beamforming transmission may be used in combination withtransmit diversity.

Generally, for MIMO systems utilizing n transmit antennas, n transportblocks may be transmitted simultaneously over the same carrier utilizingthe same channelization code. Note that the different transport blockssent over the n transmit antennas may have the same or differentmodulation and coding schemes from one another.

On the other hand, Single Input Multiple Output (SIMO) generally refersto a system utilizing a single transmit antenna (a single input to thechannel) and multiple receive antennas (multiple outputs from thechannel). Thus, in a SIMO system, a single transport block is sent overthe respective carrier.

Referring to FIG. 7, an access network 300 in a UTRAN architecture isillustrated, including one or more UEs configured with the presentapparatus or methods. The multiple access wireless communication systemincludes multiple cellular regions (cells), including cells 302, 304,and 306, each of which may include one or more sectors. The multiplesectors can be formed by groups of antennas with each antennaresponsible for communication with UEs in a portion of the cell. Forexample, in cell 302, antenna groups 312, 314, and 316 may eachcorrespond to a different sector. In cell 304, antenna groups 318, 320,and 322 each correspond to a different sector. In cell 306, antennagroups 324, 326, and 328 each correspond to a different sector. Thecells 302, 304 and 306 may include several wireless communicationdevices, e.g., User Equipment or UEs, which may be in communication withone or more sectors of each cell 302, 304 or 306. For example, UEs 330and 332 may be in communication with Node B 342, UEs 334 and 336 may bein communication with Node B 344, and UEs 338 and 340 can be incommunication with Node B 346. Here, each Node B 342, 344, 346 isconfigured to provide an access point to a CN 204 (see FIG. 5) for allthe UEs 330, 332, 334, 336, 338, 340 in the respective cells 302, 304,and 306. Further, one or more of UEs 330, 332, 334, 336, 338, 340 may bethe same as or similar to UE 10 (FIG. 1), including decoding boundaryassessment module 18 (FIGS. 1 and 2).

As the UE 334 moves from the illustrated location in cell 304 into cell306, a serving cell change (SCC) or handover may occur in whichcommunication with the UE 334 transitions from the cell 304, which maybe referred to as the source cell, to cell 306, which may be referred toas the target cell. Management of the handover procedure may take placeat the UE 334, at the Node Bs corresponding to the respective cells, ata radio network controller 206 (see FIG. 5), or at another suitable nodein the wireless network. For example, during a call with the source cell304, or at any other time, the UE 334 may monitor various parameters ofthe source cell 304 as well as various parameters of neighboring cellssuch as cells 306 and 302. Further, depending on the quality of theseparameters, the UE 334 may maintain communication with one or more ofthe neighboring cells. During this time, the UE 334 may maintain anActive Set, that is, a list of cells that the UE 334 is simultaneouslyconnected to (i.e., the UTRA cells that are currently assigning adownlink dedicated physical channel DPCH or fractional downlinkdedicated physical channel F-DPCH to the UE 334 may constitute theActive Set).

The modulation and multiple access scheme employed by the access network300 may vary depending on the particular telecommunications standardbeing deployed. By way of example, the standard may includeEvolution-Data Optimized (EV-DO) or Ultra Mobile Broadband (UMB). EV-DOand UMB are air interface standards promulgated by the 3rd GenerationPartnership Project 2 (3GPP2) as part of the CDMA2000 family ofstandards and employs CDMA to provide broadband Internet access tomobile stations. The standard may alternately be Universal TerrestrialRadio Access (UTRA) employing Wideband-CDMA (W-CDMA) and other variantsof CDMA, such as TD-SCDMA; Global System for Mobile Communications (GSM)employing TDMA; and Evolved UTRA (E-UTRA), Ultra Mobile Broadband (UMB),IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, and Flash-OFDMemploying OFDMA. UTRA, E-UTRA, UMTS, LTE, LTE Advanced, and GSM aredescribed in documents from the 3GPP organization. CDMA2000 and UMB aredescribed in documents from the 3GPP2 organization. The actual wirelesscommunication standard and the multiple access technology employed willdepend on the specific application and the overall design constraintsimposed on the system.

FIG. 8 is a block diagram of a Node B 510 in communication with a UE550, where the Node B 510 may be the Node B 208 in FIG. 5, and the UE550 may be the UE 10 in FIG. 1, executing decoding boundary assessmentmodule 18 (FIGS. 1 and 3). In the downlink communication, a transmitprocessor 520 may receive data from a data source 512 and controlsignals from a controller/processor 540. The transmit processor 520provides various signal processing functions for the data and controlsignals, as well as reference signals (e.g., pilot signals). Forexample, the transmit processor 520 may provide cyclic redundancy check(CRC) codes for error detection, coding and interleaving to facilitateforward error correction (FEC), mapping to signal constellations basedon various modulation schemes (e.g., binary phase-shift keying (BPSK),quadrature phase-shift keying (QPSK), M-phase-shift keying (M-PSK),M-quadrature amplitude modulation (M-QAM), and the like), spreading withorthogonal variable spreading factors (OVSF), and multiplying withscrambling codes to produce a series of symbols. Channel estimates froma channel processor 544 may be used by a controller/processor 540 todetermine the coding, modulation, spreading, and/or scrambling schemesfor the transmit processor 520. These channel estimates may be derivedfrom a reference signal transmitted by the UE 550 or from feedback fromthe UE 550. The symbols generated by the transmit processor 520 areprovided to a transmit frame processor 530 to create a frame structure.The transmit frame processor 530 creates this frame structure bymultiplexing the symbols with information from the controller/processor540, resulting in a series of frames. The frames are then provided to atransmitter 532, which provides various signal conditioning functionsincluding amplifying, filtering, and modulating the frames onto acarrier for downlink transmission over the wireless medium throughantenna 534. The antenna 534 may include one or more antennas, forexample, including beam steering bidirectional adaptive antenna arraysor other similar beam technologies.

At the UE 550, a receiver 554 receives the downlink transmission throughan antenna 552 and processes the transmission to recover the informationmodulated onto the carrier. The information recovered by the receiver554 is provided to a receive frame processor 560, which parses eachframe, and provides information from the frames to a channel processor594 and the data, control, and reference signals to a receive processor570. The receive processor 570 then performs the inverse of theprocessing performed by the transmit processor 520 in the Node B 510.More specifically, the receive processor 570 descrambles and despreadsthe symbols, and then determines the most likely signal constellationpoints transmitted by the Node B 510 based on the modulation scheme.These soft decisions may be based on channel estimates computed by thechannel processor 594. The soft decisions are then decoded anddeinterleaved to recover the data, control, and reference signals. TheCRC codes are then checked to determine whether the frames weresuccessfully decoded. The data carried by the successfully decodedframes will then be provided to a data sink 572, which representsapplications running in the UE 550 and/or various user interfaces (e.g.,display). Control signals carried by successfully decoded frames will beprovided to a controller/processor 590. When frames are unsuccessfullydecoded by the receiver processor 570, the controller/processor 590 mayalso use an acknowledgement (ACK) and/or negative acknowledgement (NACK)protocol to support retransmission requests for those frames.

In the uplink, data from a data source 578 and control signals from thecontroller/processor 590 are provided to a transmit processor 580. Thedata source 578 may represent applications running in the UE 550 andvarious user interfaces (e.g., keyboard). Similar to the functionalitydescribed in connection with the downlink transmission by the Node B510, the transmit processor 580 provides various signal processingfunctions including CRC codes, coding and interleaving to facilitateFEC, mapping to signal constellations, spreading with OVSFs, andscrambling to produce a series of symbols. Channel estimates, derived bythe channel processor 594 from a reference signal transmitted by theNode B 510 or from feedback contained in the midamble transmitted by theNode B 510, may be used to select the appropriate coding, modulation,spreading, and/or scrambling schemes. The symbols produced by thetransmit processor 580 will be provided to a transmit frame processor582 to create a frame structure. The transmit frame processor 582creates this frame structure by multiplexing the symbols withinformation from the controller/processor 590, resulting in a series offrames. The frames are then provided to a transmitter 556, whichprovides various signal conditioning functions including amplification,filtering, and modulating the frames onto a carrier for uplinktransmission over the wireless medium through the antenna 552.

The uplink transmission is processed at the Node B 510 in a mannersimilar to that described in connection with the receiver function atthe UE 550. A receiver 535 receives the uplink transmission through theantenna 534 and processes the transmission to recover the informationmodulated onto the carrier. The information recovered by the receiver535 is provided to a receive frame processor 536, which parses eachframe, and provides information from the frames to the channel processor544 and the data, control, and reference signals to a receive processor538. The receive processor 538 performs the inverse of the processingperformed by the transmit processor 580 in the UE 550. The data andcontrol signals carried by the successfully decoded frames may then beprovided to a data sink 539 and the controller/processor, respectively.If some of the frames were unsuccessfully decoded by the receiveprocessor, the controller/processor 540 may also use an acknowledgement(ACK) and/or negative acknowledgement (NACK) protocol to supportretransmission requests for those frames.

The controller/processors 540 and 590 may be used to direct theoperation at the Node B 510 and the UE 550, respectively. For example,the controller/processors 540 and 590 may provide various functionsincluding timing, peripheral interfaces, voltage regulation, powermanagement, and other control functions. The computer readable media ofmemories 542 and 592 may store data and software for the Node B 510 andthe UE 550, respectively. A scheduler/processor 546 at the Node B 510may be used to allocate resources to the UEs and schedule downlinkand/or uplink transmissions for the UEs.

Several aspects of a telecommunications system have been presented withreference to a W-CDMA system. As those skilled in the art will readilyappreciate, various aspects described throughout this disclosure may beextended to other telecommunication systems, network architectures andcommunication standards.

By way of example, various aspects may be extended to other UMTS systemssuch as TD-SCDMA, High Speed Downlink Packet Access (HSDPA), High SpeedUplink Packet Access (HSUPA), High Speed Packet Access Plus (HSPA+) andTD-CDMA. Various aspects may also be extended to systems employing LongTerm Evolution (LTE) (in FDD, TDD, or both modes), LTE-Advanced (LTE-A)(in FDD, TDD, or both modes), CDMA2000, Evolution-Data Optimized(EV-DO), Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi), IEEE 802.16(WiMAX), IEEE 802.20, Ultra-Wideband (UWB), Bluetooth, and/or othersuitable systems. The actual telecommunication standard, networkarchitecture, and/or communication standard employed will depend on thespecific application and the overall design constraints imposed on thesystem.

In accordance with various aspects of the disclosure, an element, or anyportion of an element, or any combination of elements may be implementedwith a “processing system” that includes one or more processors.Examples of processors include microprocessors, microcontrollers,digital signal processors (DSPs), field programmable gate arrays(FPGAs), programmable logic devices (PLDs), state machines, gated logic,discrete hardware circuits, such as a custom application-specificintegrated circuit (ASIC), and other suitable hardware configured toperform the various functionality described throughout this disclosure.One or more processors in the processing system may execute software.Software shall be construed broadly to mean instructions, instructionsets, code, code segments, program code, programs, subprograms, softwaremodules, applications, software applications, software packages,routines, subroutines, objects, executables, threads of execution,procedures, functions, etc., whether referred to as software, firmware,middleware, microcode, hardware description language, or otherwise. Thesoftware may reside on a computer-readable medium. The computer-readablemedium may be a non-transitory computer-readable medium. Anon-transitory computer-readable medium includes, by way of example, amagnetic storage device (e.g., hard disk, floppy disk, magnetic strip),an optical disk (e.g., compact disk (CD), digital versatile disk (DVD)),a smart card, a flash memory device (e.g., card, stick, key drive),random access memory (RAM), read only memory (ROM), programmable ROM(PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), aregister, a removable disk, and any other suitable medium for storingsoftware and/or instructions that may be accessed and read by acomputer. The computer-readable medium may also include, by way ofexample, a carrier wave, a transmission line, and any other suitablemedium for transmitting software and/or instructions that may beaccessed and read by a computer. The computer-readable medium may beresident in the processing system, external to the processing system, ordistributed across multiple entities including the processing system.The computer-readable medium may be embodied in a computer-programproduct. By way of example, a computer-program product may include acomputer-readable medium in packaging materials. Those skilled in theart will recognize how best to implement the described functionalitypresented throughout this disclosure depending on the particularapplication and the overall design constraints imposed on the overallsystem.

It is to be understood that the specific order or hierarchy of steps inthe methods disclosed is an illustration of exemplary processes. Basedupon design preferences, it is understood that the specific order orhierarchy of steps in the methods may be rearranged. The accompanyingmethod claims present elements of the various steps in a sample order,and are not meant to be limited to the specific order or hierarchypresented unless specifically recited therein.

The previous description is provided to enable any person skilled in theart to practice the various aspects described herein. Variousmodifications to these aspects will be readily apparent to those skilledin the art, and the generic principles defined herein may be applied toother aspects. Thus, the claims are not intended to be limited to theaspects shown herein, but is to be accorded the full scope consistentwith the language of the claims, wherein reference to an element in thesingular is not intended to mean “one and only one” unless specificallyso stated, but rather “one or more.” Unless specifically statedotherwise, the term “some” refers to one or more. A phrase referring to“at least one of” a list of items refers to any combination of thoseitems, including single members. As an example, “at least one of: a, b,or c” is intended to cover: a; b; c; a and b; a and c; b and c; and a, band c. All structural and functional equivalents to the elements of thevarious aspects described throughout this disclosure that are known orlater come to be known to those of ordinary skill in the art areexpressly incorporated herein by reference and are intended to beencompassed by the claims. Moreover, nothing disclosed herein isintended to be dedicated to the public regardless of whether suchdisclosure is explicitly recited in the claims. No claim element is tobe construed under the provisions of 35 U.S.C. §112, sixth paragraph,unless the element is expressly recited using the phrase “means for” or,in the case of a method claim, the element is recited using the phrase“step for.”

What is claimed is:
 1. A method for wireless communication, comprising:receiving, by a processor of a user equipment (UE), a data or voiceframe from a base station; selecting one or more quality metrics fordetermining a decoding boundary of the received frame; computing theselected one or more quality metrics; determining the decoding boundaryfor the received frame based on the one or more computed qualitymetrics; decoding the received frame at the determined decodingboundary; determining whether the decoding of the received frame wassuccessful; when the decoding was successful, terminating reception ofthe rest of the received frame; and when the decoding was unsuccessful,adjusting the decoding boundary and decoding the received frame at theadjusted decoding boundary.
 2. The method of claim 1, wherein thereceived frame is received using a Wideband-Code Division MultipleAccess (WCDMA) radio access technology.
 3. The method of claim 1,wherein decoding includes Viterbi decoding.
 4. The method of claim 1,wherein the one or more quality metrics are based on asignal-to-interference ratio (SIR).
 5. The method of claim 1, whereinthe one or more quality metrics are based on a symbol error rate (SER).6. The method of claim 1, wherein the one or more quality metrics arebased on Viterbi decoder paths.
 7. The method of claim 1, wherein theone or more quality metrics are based on a rate of encoding.
 8. Anapparatus for wireless communication, comprising: at least one processorconfigured to: receive a data or voice frame from a base station; selectone or more quality metrics for determining a decoding boundary of thereceived frame; compute the selected one or more quality metrics;determine the decoding boundary for the received frame based on the oneor more computed quality metrics; decode the received frame at thedetermined decoding boundary; determine whether the decoding of thereceived frame was successful; when the decoding was successful,terminate reception of the rest of the received frame; and when thedecoding was unsuccessful, adjust the decoding boundary and decode thereceived frame at the adjusted decoding boundary.
 9. The apparatus ofclaim 8, wherein the received frame is received using a Wideband-CodeDivision Multiple Access (WCDMA) radio access technology.
 10. Theapparatus of claim 8, wherein decoding includes Viterbi decoding. 11.The apparatus of claim 8, wherein the one or more quality metrics arebased on a signal-to-interference ratio (SIR).
 12. The apparatus ofclaim 8, wherein the one or more quality metrics are based on a symbolerror rate (SER).
 13. The apparatus of claim 8, wherein the one or morequality metrics are based on Viterbi decoder paths.
 14. The apparatus ofclaim 8, wherein the one or more quality metrics are based on a rate ofencoding.
 15. An apparatus for wireless communication, comprising: meansfor receiving a data or voice frame from a base station; means forselecting one or more quality metrics for determining a decodingboundary of the received frame; means for computing the selected one ormore quality metrics; means for determining the decoding boundary forthe received frame based on the one or more computed quality metrics;means for decoding the received frame at the determined decodingboundary; means for determining whether the decoding of the receivedframe was successful; means for, when the decoding was successful,terminating reception of the rest of the received frame; and means for,when the decoding was unsuccessful, adjusting the decoding boundary anddecoding the received frame at the adjusted decoding boundary.
 16. Theapparatus of claim 15, wherein the received frame is received using aWideband-Code Division Multiple Access (WCDMA) radio access technology.17. The apparatus of claim 15, wherein decoding includes Viterbidecoding.
 18. The apparatus of claim 15, wherein the one or more qualitymetrics are based on a signal-to-interference ratio (SIR).
 19. Theapparatus of claim 15, wherein the one or more quality metrics are basedon a symbol error rate (SER).
 20. The apparatus of claim 15, wherein theone or more quality metrics are based on Viterbi decoder paths.
 21. Theapparatus of claim 15, wherein the one or more quality metrics are basedon a rate of encoding.
 22. A computer program product, comprising: anon-transitory computer-readable medium comprising code for: receiving adata or voice frame from a base station; selecting one or more qualitymetrics for determining a decoding boundary of the received frame;computing the selected one or more quality metrics; determining thedecoding boundary for the received frame based on the one or morecomputed quality metrics; decoding the received frame at the determineddecoding boundary; determining whether the decoding of the receivedframe was successful; when the decoding was successful, terminatingreception of the rest of the received frame; and when the decoding wasunsuccessful, adjusting the decoding boundary and decoding the receivedframe at the adjusted decoding boundary.
 23. The product of claim 22,wherein the received frame is received using a Wideband-Code DivisionMultiple Access (WCDMA) radio access technology.
 24. The product ofclaim 22, wherein decoding includes Viterbi decoding.
 25. The product ofclaim 22, wherein the one or more quality metrics are based on asignal-to-interference ratio (SIR).
 26. The product of claim 22, whereinthe one or more quality metrics are based on a symbol error rate (SER).27. The product of claim 22, wherein the one or more quality metrics arebased on Viterbi decoder paths.
 28. The product of claim 22, wherein theone or more quality metrics are based on a rate of encoding.